> Perhaps a better criticism is the mostly useless emphasis on immutable data structures. The example I like to bring up is how Haskell for a long time didn't h

> Perhaps a better criticism is the mostly useless emphasis on immutable data structures. The example I like to bring up is how Haskell for a long time didn't have a readily-available hash table implementation for completely ideological reasons. Can you link to some evidence that the reasons were completely ideological?